1. Field of the Invention
The present invention relates to a pigment dispersion composition, a red colored composition, a colored curable composition, a color filter for a solid state imaging device and a method for producing the same, and a solid state imaging device.
2. Description of the Related Art
As color filters used for the purpose of coloration of a solid state imaging device or a liquid crystal display device, a color filter having a red filter layer, a green filter layer and a blue filter layer, and a color filter having a yellow filter layer, a magenta filter layer and a cyan filter layer, wherein the filter layers are disposed on the same plane of a substrate and adjacent to each other, are known (in the present specification, the color filter layer of each color is also referred to as a “colored pattern”).
Recently, higher microfining is desired for color filters.
However, conventional pigment dispersion system has problems of unimproved resolution, non-uniformity of color caused due to coarse particles of a pigment, and the like. Hence, the conventional pigment dispersion system is not suitable for applications like solid state imaging device, which requires a microfine pattern. To solve this problem, use of dyes has been conventionally proposed (e.g., see Japanese Patent Application Laid-Open (JP-A) No. 6-75375).
For example, it has been known to use a red dye in a red color filter array of a color filter (e.g., see JP-A No. 5-5067).
However, since the heat resistance and light resistance of a colored pattern obtained by using dyes are insufficient, use of organic pigments having excellent heat resistance and light resistance in color filters has been studied.
As a method of manufacturing a color filter using an organic pigment, there are a photolithography method in which a patterning process (including exposing and developing a composition containing an organic pigment dispersed in a photosensitive resin) is repeated a certain number of times (e.g., see, JP-A No. 1-152449), and a printing method such as offset printing or ink jet printing in which an ink containing an organic pigment is used, for example.
As an organic pigment for use in a color filter, use of an organic pigment having excellent heat resistance and light resistance, such as an anthraquinone pigment, a diketopyrrolopyrrole pigment, a quinacridone pigment, an isoindoline pigment, a perinone pigment, a perylene pigment, or a fused azo pigment, has been studied.
In International Publication No. 05/052074, a red ink composition for use in a color filter, that contains a monoazo compound having a naphthalene ring, is disclosed. Studies have been carried out to obtain a color filter having favorable spectral characteristic by using such various pigments.
Meanwhile, further microfining has been tried for the recent color filters compared to conventional ones. As the colored pattern formed by the process of manufacturing a microfine color filter is small, residues are easily generated. The residues tend to impart an adverse effect on the performance of a color filter, which is problematic.
Further, in recent days, according to miniaturization of a solid state imaging device, microfining of pigments, thinning of a colored pattern, and noise reduction in spectrophotometric spectrum are required for a color filter.
To deal with the problems, use of dyes has been suggested (e.g., see JP-A No. 6-75375). In addition, it has been known to use a red dye in a red color filter array of a color filter (e.g., see JP-A No. 5-5067).
However, since the heat resistance and light resistance of a colored pattern obtained by using dyes are insufficient, a color filter using an organic pigment having excellent heat resistance and light resistance has been studied.
As an organic pigment for use in a color filter, use of an organic pigment having excellent heat resistance and light resistance, such as an anthraquinone pigment, a diketopyrrolopyrrole pigment, a quinacridone pigment, an isoindoline pigment, a perinone pigment, a perylene pigment, or a fused azo pigment, has been studied.
In International Publication No. 05/052074, a red ink composition for use in a color filter, that contains a monoazo compound having a naphthalene ring, is disclosed.
However, there is no pigment dispersion containing a conventional red pigment such as an anthraquinone pigment or a diketopyrrolopyrrole pigment, that satisfies all of microfining of pigments, thinning of a colored pattern, and spectrophotometric spectrum.
As a method of manufacturing a color filter using an organic pigment, there are a photolithography method in which a patterning process (including exposing and developing a composition containing an organic pigment dispersed in a photosensitive resin) is repeated a certain number of times (e.g., see, JP-A No. 1-152449) and a printing method such as offset printing or ink jet printing in which an ink containing an organic pigment is used, for example.